Surgical drape including a layer to protect the operator from scattered radiation during cardiologic and radiologic invasive procedures

ABSTRACT

Invasive cardiology and radiology are widespread procedures that involve the use of X-ray radiations for imaging. During these procedures, the operators are exposed to a variable dose of radiation. It is shown that these professionals are among the most exposed to ionizing radiations. New studies have shown that brain cancers can be linked to these exposures. As these exposures are harmful to health, maximum protection is required to protect the patient and the staff. The current invention provides an improved protective shield to fully protect the staff in cardiologic, angiologic, and radiologic procedures. The present invention relates to a modified surgical drape that include a layer that absorbs the X-rays scattered from the patient&#39;s body during invasive angiology procedures.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/812,684, filed Nov. 14, 2017, which claims the benefit of U.S.provisional Application 62/474,651, filed Mar. 22, 2017, both of whichare herein incorporated by reference in their entirety.

DESCRIPTION OF THE BACKGROUND ART

In many medical procedures, X-ray live imaging of the patient isnecessary to guide the operator. However, X-rays are well known to becarcinogenic and to induce various health damage. It is thus alwaysdesirable to minimize the exposure to X-rays, both for the patient andthe operator. The X-ray dose delivered to the patient, for a specifictype of X-ray machine, depends directly on the imaging time. It is theresponsibility of the operator to minimize the exposure time by avoidingunnecessary imaging. As far as the operator is concerned, the problem issimilar. There is obviously no need for the operator to be exposed andall measures are usually taken to reduce the X-rays dose on the operatorand other members of the staff. Moreover, the staff is exposed to X-rayson a daily basis as opposed to the patient, who undergoes only sporadicexposure. Protection of the staff is thus regarded as a very importantissue by health authorities.

In angioplasty procedures, X-ray imaging is typically performed with amachine that has an X-ray source on one side of the patient and adetector on the opposite side. The whole machinery can rotate and imagethe patient's body under various angles. When no patient is presentbetween the source and the detector, most of the X-rays travel directlyfrom the source to the detector. When the patient is present, part ofthe X-ray radiation still reaches the detector, where its intensity isrecorded to compose the image delivered to the operator. However, inthat case, a significant part (typically as high as 30%) of the X-raysare scattered by the patient's body and form what is commonly referredto as the secondary radiation. The secondary radiation is diffuse andmay travel in all possible directions from the patient's body thusirradiating the surrounding staff.

Up to now, various devices have been used to screen the secondaryradiation. These devices include rigid screens that can be slid over thepatient, but also soft pads of various size and shape to be placedmanually by the operator where required.

Radiation shielding placed directly on the patient can decrease scatter.One such shield is a small bismuth-based disposable shield (RADPAD,Worldwide Innovations and Technologies). When placed between the patientand the operator and outside of the primary beam, this shield can reduceoperator doses by 44%. Meisinger et al., AJR:207, October 2016, 745-754.Small, lightweight disposable cloths with a 0.1-mm lead equivalencydecreased scattered radiation to one-ninth to one-fifth of the originalvalue with an increase overall patient entrance exposure rate of 30-40%,owing to compensating radiation beam adjustments made by the automaticexposure control. Id. Proper positioning is key, because placement ofthis or any high attenuation object in the path of the primary beam canmarkedly increase radiation to the patient through automatic exposurecontrol. Id.

As the radiation is diffuse, the protective gear has to cover allpossible radiation angles. In practice, this has been difficult toachieve, partly because the imaging machinery needs to move around thepatient, and the operator needs to have unobstructed access to differentparts of the patient. The above-mentioned free-standing protecting padscan be placed directly on the patient to fill the gaps. However, sincethe operator cannot see the X-ray secondary radiation that still leaksthrough the patchy barrier composed of those different devices, theoperator does not always know how to place the free-standing pads oreven which one to use. For example, one particular gap that has beenspotted in recent studies is the region of the patient arm close to theoperator. Kallinikou et al., Am J Cardiol. 118(2):1 88-94, 2016. A largeamount of diffuse radiation leaks through the gap, and it is practicallydifficult to cover it due to its proximity to the edge of the table.Presently, a large radio-protective sheet for cardiology and angiologysurgery does not exist on the market.

Thus, there is a need in the art for better radio-protection for theprotection of operators. The invention fulfills this need.

BRIEF SUMMARY OF THE INVENTION

The invention encompasses a sterile surgical drape comprising anintegrated radio-protective layer. Preferably, the surgical drape is atleast 130 cm in width and at least 130 cm in length. Most preferably,the integrated radio-protective layer is at least 130 cm in width and atleast 60 cm in length.

In some embodiments, the integrated radio-protective layer, and theassociated surgical drape, has at least one or two precut hole(s) thatcan be opened, and preferably closed afterwards, to allow access to thepatient.

In some embodiments, the integrated radio-protective layer comprises atleast one precut hole of at least 5 cm in diameter.

In some embodiments, the integrated radio-protective layer comprises atleast two precut holes of at least 5 cm in diameter and separated bybetween 90 cm and 110 cm.

In some embodiments, the integrated radio-protective layer comprises atleast two precut holes of at least 5 cm in diameter and separated bybetween 20 cm and 50 cm.

In some embodiments, the integrated radio-protective layer comprises atleast two precut holes of at least 5 cm in diameter and separated bybetween 50 cm and 90 cm.

In some embodiments, the integrated radio-protective layer comprises atleast two precut holes of at least 5 cm in diameter and separated bybetween 90 cm and 110 cm and at least two precut holes of at least 5 cmin diameter and separated by between 20 cm and 50 cm.

In some embodiments, the precut holes are between 5 cm and 15 cm indiameter.

In some embodiments, the sterile surgical drape further comprises atleast two rectangular extensions of the precut holes of at least 5 cm by10 cm.

In some embodiments, the integrated radio-protective layer comprises ahole of at least 30 cm×30 cm, preferably between 30 cm×30 cm and 40cm×50 cm.

In some embodiments, the surgical drape is at least 190 cm in length. Insome embodiments, the surgical drape is at least 250 cm in length.

In some embodiments, surgical drape is at least 200 cm in width.

In some embodiments, the integrated radio-protective layer has at least0.25 mm lead equivalence at 70 kVp.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings herein illustrate the present invention, wherein:

FIG. 1A-C: Illustrative embodiment of surgical drape typically used inangioplasty operations. A) Schematic of part of a surgical drape for usein angioplasty operations. 1) Hatched area indicates the region coveredby the radio-protecting layer. 2) The dotted lines indicate the pre-cutaccess ports in the drape. 3) Areas of the drape free ofradio-protection for imaging a longer portion of the artery. 4)Conventional surgical drape. 5) lateral plastic flaps (included in aconventional surgical drape). (B) Photograph of a surgical drape areacorresponding to the portion shown in A. (B): Photograph of a completesurgical drape.

FIG. 2A-B: Results of surgical drapes comprising an integratedradio-protective layer versus RADPADs in various coronary interventions.

FIG. 3: An embodiment (SEPARCATH) showing exemplary measurements of theradio-protective layer of a device of the invention. Possible positionsand sizes for precut access ports are shown. The size of the steriledrape is not drawn to scale—it need only be larger than theradio-protective layer and at least 100 cm×100 cm.

FIG. 4: An embodiment (SEPARPACE) showing exemplary measurements of theradio-protective layer of a device of the invention. Possible positionsand sizes for precut rectangles are shown. The size of the sterile drapeis not drawn to scale—it need only be larger than the radio-protectivelayer and at least 100 cm×100 cm.

FIG. 5: An embodiment (SEPARVASC) showing exemplary measurements of theradio-protective layer of a device of the invention. The possibleposition and size for a precut rectangle are shown. The size of thesterile drape is not drawn to scale—it need only be larger than theradio-protective layer and at least 100 cm×100 cm.

DETAILED DESCRIPTION OF THE INVENTION

The present invention specifically matches the need of minimizing theX-ray diffuse radiation from the patient's body. The invention relatesto a new type of surgical drape that includes a radio-protecting layer.This layer stops the radiation in places that were usually uncovered,either because there was no suitable device to stop it, or because theoperator was not aware of the radiation emanating from that location.Because of its large coverage, the drape offers an almost fullprotection for the operator and the assistant.

The drape of the invention has two components. The first is a commonsterile surgical drape. The second is the radio-protection layer—aradiation absorbing sheet integrated into the surgical drape. Theradio-protection layer is not present over the full extent of the drape,but only in the strategic regions. The radio-protection layer is alsosterile.

The common sterile surgical drape provides surgical light sterileprotection. In some embodiments, it can cover the whole patient and thetable of examination, which aim is sterility protection. Theradio-protection layer is able to stop all or most of scatteredradiation from the patient.

In various embodiments, the radiation absorbing sheet has pre-cut holesthat can be opened to allow access to the patient and allow the operatorto choose the convenient site for the intervention. For example, theholes can allow access to the left arm (LA), right arm (RA), leftfemoral (LF) or right femoral (RF) approach, before initiating theprocedure by simple opening of the pre-cut hole. In this way, theinvention provides a Specific Electromagnetic operator combined sterileProtection drape Against scattered Radiation (SEPAR).

Integrating the radio-protection layer within the drape offers numerousadvantages. The invention offers larger and more reliable coverage sincethe operator does not always know where to effectively place smallerforms of radio-protection. Smaller forms of radio-protection can disturbthe procedure since it may have to be moved, as opposed to the surgicaldrape, which is present anyway. The smaller forms of radio-protectioncan slide by accident, particularly when located on the side of thepatient.

It was surprisingly found that this new radio-protective device couldreduce operator exposure by 90% compared to RADPADs and completelyeliminate operator and assistant exposure in many cases. It wasunexpected that use of the present invention would result in such alarge increase in radio-protection for the operator and assistant, sinceit was previously assumed that the smaller forms of radio-protectionwere adequate in most circumstances. The impressive degree of increasedprotection offered by the integrated radio-protection layer wassurprising and was not expected.

Surgical Drape

The invention encompasses a surgical drape comprising an integratedradio-protective layer. The surgical drape is sterile. Theradio-protection layer does not move independently from the surgicaldrape.

Surgical drapes are well-known in the art and can be made of manymaterials (e.g., U.S. Pat. Nos. 9,487,893, 9,416,485, and 8,079,365,which are hereby incorporated by reference). Surgical drapes areavailable commercially, for examples from Cardinal Health, Arc Royal, orKimberly-Clark.

In various embodiments, the surgical drape has a width (i.e. from sideto side of the patient) of at least 100, 110, 120, 130, 140, 150, 160,170, 180, 190, 200, 210, 220, 230, 240, or 250 cm.

In various embodiments, the surgical drape has a length (i.e. from headto feet of the patient) of at least 100, 110, 120, 130, 140, 150, 160,170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 280, 300, 320, 340,360, 380, or 400 cm. Each and every combination of width and height isspecifically contemplated.

Most preferably, the surgical drape has a width of at least 130 cm and alength of at least 130 cm.

Preferably, the drape is of sufficient width to fully cover the patientfrom side to side, including the arms of the patient. Preferably, thedrape is of sufficient length to fully cover the patient from head, orneck, to feet.

Radio-Protection Layer

Within the context of this invention, a radio-protective layer is alayer of an X-ray absorbing compound that prevents the passage of atleast ½ of the X-ray radiation at 70 kVp.

In various embodiments, the radio-protection layer has a width (i.e.from side to side of the patient) of at least 100, 110, 120, 130, 140,150, 160, 170, 180, 190, or 200 cm. Preferably, the radio-protectionlayer is of sufficient width to fully cover the patient from side toside, including the arms of the patient.

In various embodiments, the radio-protection layer has a length (i.e.from head to feet of the patient) of at least 40, 50, 60, 70, 80, 90,100, 110, or 120 cm. Each and every combination of width and height isspecifically contemplated. In addition, each and every combination ofsize of radio-protection layer with a larger size of surgical drape isspecifically contemplated

Most preferably, the radio-protection layer has a width of at least 130cm and a length of at least 60 cm or 80 cm or 130 cm.

The radio-protection layer can be integrated into the surgical drapewithin existing layers of the surgical drape or as an additional layer.Preferably, the surgical drape retains its absorbency and imperviousnessto liquids.

The radio-protection layer can be made of any X-ray absorbing compound.Preferably, the X-ray absorbing compound is essentially free of lead. Insome embodiments, the X-ray absorbing compound is a metal powder forexample bismuth oxide [Bi₂O₃], antimony, gadolinium oxide [Gd₂O₃], orbarium sulfate [BaSO]). In one embodiment, the X-ray absorbing compoundis a BaSO—Bi₂O₃ composite. The X-ray absorbing compound can compriseblend of metals and minerals including tungsten, tin, antimony, ceriumoxide and trace metals other than lead.

Preferred compounds can be found in radio-protective materials sold asKIARMOR (Infab Corp.), SORBX (AngioSystems, Inc.), RADPAD (WorldwideInnovations & Technologies, Inc.), and WIROMA (Lanz-Ankiler AG) devices.

In various embodiments, the integrated radio-protective layer has atleast 0.05, 0.1, 0.2, 0.25, 0.3, 0.35, 0.4, or 0.5 mm lead equivalenceat 70 kVp. Preferably, the integrated radio-protective layer has between0.20, 0.25, or 0.30 and 0.25, 0.30, or 0.35 mm lead equivalence at 70kVp. More preferably, the integrated radio-protective layer has between0.20 and 0.30, most preferably, 0.25, mm lead equivalence at 70 kVp.

Preferably, the integrated radio-protective layer provides a 10-foldincrease in protection of the operator and/or assistant as compared to a37 cm×42 cm RADPAD, determined using the procedures in the Examples or acomparable procedure.

Precut Holes

In various embodiments, the radio-protection layer, and the associatedsurgical drape, comprises at least one, two, three, or four precuthole(s) that allows access to the patient. In some embodiments, theholes are permanently placed and do not need to be opened. In otherembodiments, precut holes can be can be opened to allow access to thepatient.

In some embodiments, the precut holes can be closed after allowingaccess to the patient. In some embodiments, a flap may be employed toallow opening and closing of the precut holes.

In various embodiments, the integrated radio-protective layer comprisesat least one precut circular hole of at least 5, 6, 7, 8, 9, 10, 11, 12,13, 14, or 15 cm in diameter. In various embodiments, the integratedradio-protective layer comprises at least two precut circular holes ofat least 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 cm in diameter.Preferably, the holes are separated by between 20 cm and 110 cm asmeasured from the center to center of the holes.

In various embodiments, the integrated radio-protective layer comprisesat least two precut circular holes of at least 5, 6, 7, 8, 9, 10, 11,12, 13, 14, or 15 cm in diameter and separated by between 90 cm and 110cm as measured from the center to center of the holes. In variousembodiments, the precut holes are square or rectangular and of at least5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 cm in width and length.

In various embodiments, the integrated radio-protective layer comprisesat least two precut holes of at least 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,or 15 cm in diameter and separated by between 20 cm and 50 cm asmeasured from the center to center of the holes. In various embodiments,the precut holes are square or rectangular and of at least 5, 6, 7, 8,9, 10, 11, 12, 13, 14, or 15 cm in width and length.

In various embodiments, the integrated radio-protective layer comprisesat least two precut circular holes of at least 5, 6, 7, 8, 9, 10, 11,12, 13, 14, or 15 cm in diameter and separated by between 50 cm and 90cm as measured from the center to center of the holes. In variousembodiments, the precut holes are square or rectangular and of at least5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 cm in width and length.

In various embodiments, the integrated radio-protective layer comprises(1) at least two precut holes of at least 5, 6, 7, 8, 9, 10, 11, 12, 13,14, or 15 cm in diameter and separated by between 90 cm and 110 cm, asmeasured from center to center, and (2) at least two precut holes of atleast 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 cm in diameter andseparated by between 20 cm and 50 cm, as measured from center to center.In various embodiments, the integrated radio-protective layer furthercomprises at least two rectangular extensions of the precut holes.Preferably, the rectangular extensions are of at least 5, 6, 7, 8, 9,10, 11, 12, 13, 14, or 15 cm by 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15cm. Each and every combination of numbers and sizes of holes andextensions is specifically contemplated.

In some embodiments, the integrated radio-protective layer comprises aprecut square or rectangular hole of at least 30 cm×30 cm. The hole canprovide access for surgical intervention and/or imaging. The precut holeis preferably between 30 cm×30 cm and 50 cm×50 cm, more preferablybetween 30 cm×30 cm and 30 cm×40 cm, 30 cm×50 cm, or 40 cm×50 cm.Examples are shown in FIG. 4 and FIG. 5. The area of the hole is lessthan 50% of the area of the radio-protective layer, preferably, lessthan 25%, 20%, 15%, 10% or 5% of the area of the radio-protective layer.

In some embodiments, the integrated radio-protective layer comprises (1)a precut hole of at least 30 cm×30 cm and (2) an additional connectedhole of at least 10×10 cm. The additional connected hole is preferablybetween 10 cm×10 cm and 20 cm×30 cm, more preferably between 10 cm×15 cmand 15 cm×15 cm, 15 cm×20 cm, or 20 cm×20 cm. An example is shown inFIG. 4. The sum of the area of the hole and the an additional connectedhole is less than 50% of the area of the radio-protective layer,preferably, less than 25%, 20%, 15%, 10% or 5% of the area of theradio-protective layer.

Methods and Uses

The invention encompasses the use of the drape of the invention forshielding an operator and/or assistant from radiation during a surgicalprocedure. Thus, the invention encompasses the drape of the inventionfor shielding an operator and/or assistant from radiation during asurgical procedure.

The invention further encompasses methods of using the drape of theinvention for shielding an operator and/or assistant from radiationduring a surgical procedure. In various embodiments, the drape of theinvention is spread over the patient to provide shielding. The operatorand assistant are protected from radiation when the patient isirradiated.

In one embodiment, the invention encompasses the use of the drape of theinvention for catheterization procedures. A suitable device forperforming such a procedure is shown in FIG. 3 (SEPARCATH).

In one embodiment, the invention encompasses the use of the drape of theinvention for pacemaker and/or defibrillator procedures. A suitabledevice for performing such a procedure is shown in FIG. 4 (SEPARPACE).

In one embodiment, the invention encompasses the use of the drape of theinvention for vascular procedures. A suitable device for performing sucha procedure is shown in FIG. 5 (SEPARVASC).

EXAMPLES Sterile Surgical Drape Comprising an IntegratedRadio-Protective Layer

0.25 mm lead equivalent X-LIGHT WIROMA radio-protective film was cut toan appropriate shape and taped onto a regular commercially availablesurgical drape. Openings in the radio-protective film were made to facethe openings in the surgical drape to generate surgical drapes as shownin FIG. 1. The drape of FIG. 1 has a radio-protective layer ofapproximately 130 cm by 60 cm=7800 cm². The drapes were compared toRADPADS (37 cm×42 cm=1554 cm²) placed over the access site in eachprocedure to reduce scatter radiation in various coronary interventionsusing left radial access, right radial access, or right femoral access.The surgical drapes were effective in eliminating movement of theradio-protection during the procedure.

The exposure to the operator and assistant were measured by the use ofdosimeters (DoseAware; Philips Healthcare, Best, The Netherlands)positioned on the sternum, outside the lead apron. The dosimeters aresilicon-based semi-conductor detectors with a dose-response between 1mSv and 10 Sv, in steps of 1 mSv (calibrated in ambient equivalent doseHp(10)) and a temporal resolution of 1 second. The following parameterswere recorded for each procedure: (1) operator CD through the use ofdedicated readout software (DoseView), measured by the individualdosimeters; (2) FT; (3) number of cine angiograms (NC); and (4) theDAP-normalized CD defined as the dose (mSv) received by the operatorwith each Gycm2 applied to the patient (known as the exposure factor)has been advocated and applied to our study as it isolates differencesin patient radiation among the 3 vascular access sites. The results areshown in FIGS. 2A-C.

Using RADPADS, the average cumulative dose of the operator wasapproximately 16 μSv, with a range of 4-43 μSv. Unexpectedly, using thesterile surgical drapes comprising an integrated radio-protective layer,the average cumulative dose of the operator was reduced to approximately1.4 μSv, with a range of 0-5 μSv. Surprisingly, in three of the fiveprocedures conducted with the drape of the invention, no cumulative doseof the operator was detected at all. Thus, the drape of the inventionnearly eliminated operator exposure, causing a more than 10-foldreduction in exposure compared to the RADPADS. The drape of theinvention also reduced assistant exposure. Surprisingly, in four of thefive procedures conducted with the drape of the invention, no cumulativedose of the assistant was detected at all.

Thus, it was surprising to find that the drape of the invention nearlyeliminated operator and assistant exposure during these procedures.

Similar results were seen using a 0.35 mm lead equivalentradio-protective film. However, this material adds considerable weightto the surgical drape.

We claim:
 1. A method for shielding an operator from radiation during acoronary intervention procedure of a patient with X-ray imagingcomprising spreading a sterile surgical drape over the patient toprovide shielding, wherein the sterile surgical drape comprises anintegrated radio-protective layer that does not move independently fromthe sterile surgical drape and that does not lie in the path of theprimary X-ray beam during the coronary intervention procedure, whereinthe sterile surgical drape is at least 130 cm in width and at least 130cm in length, wherein the integrated radio-protective layer is at least130 cm in width, and wherein the integrated radio-protective layer is atleast 60 cm in length, wherein the integrated radio-protective layercomprises at least one precut hole that can be opened to allow access tothe patient; and performing the coronary intervention procedure withX-ray imaging, wherein the sterile surgical drape reduces the cumulativedose of the operator of the coronary intervention procedure to 0-5 μSvwhen accessed through the right radial artery.
 2. The method of claim 1,wherein the integrated radio-protective layer has at least two precutholes that can be opened to allow access to the patient.
 3. The methodof claim 2, wherein the integrated radio-protective layer comprises atleast two precut holes of at least 5 cm in diameter and separated bybetween 90 cm and 110 cm.
 4. The method of claim 2, wherein theintegrated radio-protective layer comprises at least two precut holes ofat least 5 cm in diameter and separated by between 20 cm and 50 cm. 5.The method of claim 2, wherein the integrated radio-protective layercomprises at least two precut holes of at least 5 cm in diameter andseparated by between 50 cm and 90 cm.
 6. The method of claim 2, whereinthe integrated radio-protective layer comprises at least two precutholes of at least 5 cm in diameter and separated by between 90 cm and110 cm and at least two additional precut holes of at least 5 cm indiameter and separated by between 20 cm and 50 cm.
 7. The method ofclaim 2, wherein the precut holes are between 5 cm and 15 cm indiameter.
 8. The method of claim 2, further comprising at least tworectangular extensions of the precut holes of at least 5 cm by 10 cm. 9.The method of claim 1, wherein the integrated radio-protective layercomprises a hole of at least 30 cm×30 cm for passage of the primaryX-ray beam.
 10. The method of claim 9, wherein the hole is between 30cm×30 cm and 40 cm×50 cm.
 11. The method of claim 1, wherein thesurgical drape is at least 190 cm in length.
 12. The method of claim 11,wherein the surgical drape is at least 250 cm in length.
 13. The methodof claim 12, wherein the surgical drape is at least 200 cm in width. 14.The method of claim 1, wherein the integrated radio-protective layer hasat least 0.25 mm lead equivalence at 70 kVp.
 15. The method of claim 1,wherein the sterile surgical drape reduces the cumulative dose of theoperator of the coronary intervention procedure accessed through theright radial artery to 0-4 μSv.
 16. The method of claim 1, wherein thesterile surgical drape reduces the cumulative dose of the operator ofthe coronary intervention procedure accessed through the right radialartery to less than 5 μSv.
 17. The method of claim 1, wherein thesterile surgical drape reduces the cumulative dose of the operator ofthe coronary intervention procedure accessed through the right radialartery to 0-2 μSv.
 18. The method of claim 1, wherein the sterilesurgical drape reduces the cumulative dose of the operator of thecoronary intervention procedure accessed through the right radial arterysuch that no cumulative dose of the operator is detected.
 19. The methodof claim 1, wherein the sterile surgical drape reduces the cumulativedose of an assistant of the coronary intervention procedure accessedthrough the right radial artery such that no cumulative dose of theassistant is detected.